计算3_(k;m*Y1s/f(p+Q/x;S
1000+999-998-997+996+995-994-993……+108+107-106-105+104+103-102-1013_(k;m*Y1s/f(p+Q/x;S
算式：提示,}*G0?+g'].R/M7B1d3_(k;m*Y1s/f(p+Q/x;S
=/u6H;|6B)W7Q4w,W3_(k;m*Y1s/f(p+Q/x;S